To date, a current sensor core formed by bending a plate member made of a magnetic body has been proposed in, for example, PTL 1. Specifically, PTL 1 proposes a core including a core main body configured of a bent plate member, and a gap portion in which two end portions of the bent plate member are disposed opposing across a predetermined gap.
The core main body has an inclined portion inclined in which the dimension in the short dimension direction of the plate member, that is, the width dimension of the plate member, decreases from the side opposite from the gap portion to a connection between the gap portion and the core main body. Meanwhile, the width dimension of the plate member is constant in the gap portion.